Not Applicable
Not Applicable
The industry is constantly seeking to improve the processes used to manufacture integrated circuits from wafers. The improvements come in various forms but, generally, have one or more objectives as the desired goal. The objectives of many of these improved processes include: 1) decreasing the amount of time required to process a wafer to form the desired integrated circuits; 2) increasing the yield of usable integrated circuits per wafer by, for example, decreasing the likelihood of contamination of the wafer during processing; 3) reducing the number of steps required to turn a wafer into the desired integrated circuits; and 4) reducing the cost of processing the wafers into the desired integrated circuit by, for example, reducing the costs associated with the chemicals required for the processing.
In the processing of wafers, it is often necessary to subject one or more sides of the wafer to a fluid in either liquid, vapor or gaseous form. Such fluids are used to, for example, etch the wafer surface, clean the wafer surface, dry the wafer surface, passivate the wafer surface, deposit films on the wafer surface, etc. Control of the physical parameters of the processing fluids, such as their temperature, molecular composition, dosing, etc., is often quite crucial to the success of the processing operations. As such, the introduction of such fluids to the surface of the wafer occurs in a controlled environment. Typically, such wafer processing occurs in what has commonly become known as a reactor.
Various reactor constructions and configurations are known and used in the industry. One such reactor is used by Semitool, Inc., and is employed in their Equinox(copyright) brand processing tools. Generally stated, the reactor is comprised of a cup assembly that includes a fixed cup that is constructed from a material that does not chemically react with the processing fluids that are to be used for the particular wafer processing steps. Within the cup, a plurality of nozzles, or other means for introducing fluid into the cup, are provided. The fixed cup has an open top portion. A rotor head assembly that supports the wafer is used to seal the top of the cup to define a processing chamber in which the wafer is housed for processing. In addition to introducing the wafer into the processing chamber, the rotor head assembly may be used to spin the wafer during introduction of the processing fluid onto the surface of the wafer, or after processing to thereby remove the processing fluid.
During processing, the wafer is presented to the rotor head assembly by a robotic device that operates in a substantially clean environment in which a number of processing reactors are present. The robotic device presents the wafer in an exposed state to the rotor head assembly in an orientation in which the side of the wafer that is to be processed is faced up. The rotor head assembly inverts the wafer and engages and seals with the cup for processing. As the wafer is processed, the wafer is oriented so that the side of the wafer being processed is faced down.
The foregoing reactor construction and configuration is quite useful for many of the fluid processing steps employed in the production of an integrated circuit. The present inventor, however, has recognized that demands for future integrated circuit manufacturing processes may ultimately require more control and economic efficiency from the reactor. As such, a substantially new approach to processing and reactor design has been undertaken which provides greater control of the fluid processes currently used in connection with integrated circuit manufacturing, and, further, provides for the implementation and execution of more advanced and improved processes.
An apparatus for processing a workpiece in a micro-environment is set forth. The apparatus includes a rotor motor and a workpiece housing. The workpiece housing is connected to be rotated by the rotor motor. The workpiece housing further defines a substantially closed processing chamber therein in which one or more processing fluids are distributed across at least one face of the workpiece by centripetal accelerations generated during rotation of the housing.
In accordance with one embodiment of the apparatus, the workpiece housing includes an upper chamber member having a fluid inlet opening and a lower chamber member having a fluid inlet opening. The upper chamber member and the lower chamber member are joined to one another to form the substantially closed processing chamber. The processing chamber generally conforms to the shape of the workpiece and includes at least one fluid outlet disposed at a peripheral region thereof. At least one workpiece support is provided. The support is adapted to support a workpiece in the substantially closed processing chamber in a position to allow centripetal acceleration distribution of a fluid supplied through the inlet opening of the upper chamber member across at least an upper face of the workpiece when the workpiece housing is rotated. The wafer is further positioned by the support to allow centripetal acceleration distribution of a fluid supplied through the inlet opening of the lower chamber member across at least a lower face of the workpiece during the rotation. The at least one fluid outlet is positioned to allow extraction of fluid in the processing chamber through the action of centripetal acceleration.